The garden was conceived by Oregon Journal editor Jesse A. Currey in 1915 and approved by Portland Parks in 1917. It started as a safe haven for hybrid roses grown in Europe during World War I. Flowers began arriving in Portland in 1918 and the garden and amphitheater were dedicated in 1924. The grounds are split into several smaller areas: the Royal Rosarian Garden, the Shakespeare Garden and the Miniature Rose Garden.

The American Garden Rose Selection (AGRS) test garden covers two terraces of the Rose Garden. The roses testing in the garden are identified by number rather than by name; the plants are evaluated for two years by multiple criteria before being judged.

The Gold Award Garden, dedicated in 1970, features award-winning roses from the AGRS Test Garden. The garden features a gazebo added in 1991, and a wall honoring past presidents of the Portland Rose Society. It is a popular site for weddings.

The Royal Rosarian Garden displays roses honoring past Prime Ministers of the Royal Rosarians, a civic group that serves as the official greeters and goodwill ambassadors for the City of Portland who serve in the many Rose Festival events, and features a stone bench honoring Jesse Currey. The Royal Rosarian Garden contains many roses that are no longer commercially available.

Established in 1975, the Miniature Rose Garden is a testing ground to help determine what miniature roses will go to market. The Miniature Rose Garden is one of only eight such miniature rose testing grounds for the American Rose Society. The national annual American Rose Society winners are displayed in the middle of the garden along the center aisle.

The Shakespeare Garden was donated by the Shakespeare Society in 1943. It originally featured botanicals mentioned in the works of William Shakespeare. Over time, the Shakespeare Garden has evolved, planted with summer annuals, tropical plants, year-round shrubs, and roses. The rose varieties are named after characters in Shakespeare's plays. The Shakespeare Garden includes a formal walkway and a raised sitting area.

According to travelportland.com